Perfectly balanced double-acting reciprocating machine

ABSTRACT

A perfectly balanced reciprocating engine comprising at least one linear reciprocating rod and a rotating and revolving crank mechanism. The crank mechanism has a crank radius l and rotates about a crank axis and also revolves about another axis having an eccentricity-l from the crank axis in the opposite direction of crankshaft rotation to effect a linear reciprocating motion with a stroke 4l. The crank mechanism further comprises a balance weight of mass positioned m1 at the opposite side of the crank pin and at a distance R1 from the crank and also another balance weight of mass m2 secured to a rotatably mounted eccentric collar to effect revolution of the crank directly in the opposite side of the crankshaft positioned at a distance R2 from the crank axis. Both balance weights are determined to satisfy the formulae ml m1R1 and (m+m1 m3)l m2R2 wherein, m is the reciprocating mass, m3 is the total rotating mass except for the masses ml and m2 and l is the crank radius. The engine according to the invention provides a perfectly balanced operation.

United States Patent [54] PERFECTLY BALANCED DOUBLE-ACTING 3,258,9927/1966 Hittell 123/55 3,277,743 10/1966 Kell 123/55 3,329,134 7/1967Llewellyn 123/55 Primary Examiner-Wendell E. Burns Attorney-Robert ElBurns ABSTRACT: A perfectly balanced reciprocating engine comprising atleast one linear reciprocating rod and a rotating and revolving crankmechanism. The crank mechanism has a crank radius 1 and rotates about acrank axis and also revolves RECIPROCATING MACHINE about another axishaving an eccentricity-l from the crank axis In the opposite directionof crankshaft rotation to effect a 9 Claims, 8 Drawing Figs.

linear reciprocating motion with a stroke 41. The crank U.S. Cl.mechanism further comprises a balance weight of mass posi- 123/51123/53, 123/55 tioned m at the opposite side of the crank pin and at a[51] Illl. Cl. 75/06, distance R from the crank and also another balanceweight of Fozb F02) 25/08 mass m secured to a rotatably mountedeccentric collar to ef- [50] Fleld of Search 123/53, 51, f m r volutionof the crank directly in the opposite side of the 55 192 crankshaftpositioned at a distance R from the crank axis. Both balance weights aredetermined to satisfy the formulae [56] References C'ted ml=m and (m+m=m )l =I1l2R wherein, m is the re- UNITED STATES PATENTS ciprocatingmass, m is the total rotating mass except for the l,090,647 3/1914 Pitts123/53 masses m, and m and I is the crank radius. The engine accord-3,175,544 3/1965 Hughes l23/55 ing to the invention provides a perfectlybalanced operation.

4 2o l as l3 l9I7 I I P 24 O i 27 A 26 m 4 saw 2 UF 8 PATENTEBFEBIBIQHsum 9 UF 3 Fig. 4

PERFECTIJY BALANCED DOUBLE-ACTING RECIPROCATING MACHINE The presentinvention relates to a reciprocating machine, and more particularly to aperfectly balanced reciprocating engine providing one ormore linearlyreciprocating rods and a rotating and revolving crank mechanism.

Known reciprocating engines provide conventional crank mechanismsincluding one or more connecting rods which oscillate on a planevertical to rotating axis at every rotation of the crank by such anarrangement, it is very difficult to utilize the opposite side of thepiston to the combustion chamber as a compression chamber. Furthermore,unbalanced forces caused by inertia of the reciprocating mass of theconventional engine cannot be theoretically balanced, so that avibration problem usually accompanies the known engine.

The present invention utilizes a crank mechanism having a crank radius Irotating about a crank axis and revolving about another axis at aneccentric distance I from the crank axis in the opposite direction ofthe crankshaft rotation to effect linear reciprocating motion of the rodconnected with the crank pin with a stroke of 41 The crank mechanismfurther provides a balance weight of mass m, positioned directly on theopposite side of the crank pin about its axis at a distance R, from thecrank axis and another balance weight of mass m, secured to a rotatablymounted eccentric collar to effect revolution of the crank directly inthe opposite side of the crankshaft about its axis at distance R, fromits axis. Both balance weights are determined in accordance with theformulas ml=m R, and (m-i-m +m l =m,R,, wherein m is the reciprocatingmass, m,, is the rotating mass (rotating mass of rotating portion exceptthe equivalent reciprocating mass and the balance mass), and l is thecrank radius or amount of eccentricity. Thus, the machine or engine isprovided with a linearly reciprocating rod and the engine istheoretically balanced. The principle of the-perfect balancing isdescribed in the relating application of the same inventors.

The primary object of the present invention is to provide a dcubleactinginternal combustion engine utilizing both sides of the piston ascombustion chambers and being perfectly balanced as to unbalancedforces.

Another object of the present invention isto provide double-actinginternal combustion engine, providing aligned. two cylinders andstraightly reciprocating integrally providable rods, the underside ofthe pistons being utilized as precompression chamber of the two cycleengine, and the unbalanced forces being perfectly balance According to afeature of the. present invention a perfectly balanced reciprocatingmachine comprises a casing, at least one cylinder means having cylinderhead means and secured to the casing, wall means secured to saidcylinder means to define a space between said cylinder head and thecasing, piston means slidably accommodating in the cylinder means anddefining said space'into two working spaces by the both two-cyclereciprocating engine crankshaft having a planetary motion system byeccentric gear according to one embodiment of the present invention,

FIG. 2 shows a sectional view along; line 2-2 of FIG. 1,

FIG. 3 shows a longitudinal sectional view of a single cylinderdouble-acting perfectly. balanced two-cycle reciprocating engine ofcrankshaft planetary motion system by internal gear according to thesecond embodiment of the present invention,

FIG. 4 shows a sectional view along line 4-4 of FIG. 3,

FIG. 5 shows a longitudinal sectional view of an opposedcylindersdouble-acting perfectly balanced two-cycle reciprocating engine ofcrankshaft planetary motion system by eccentric gear according to thethird embodiment of the present invention,

FIG. 6 shows a sectional view along line 645 of FIG. 5,

FIG. 7 shows alongitudinal sectional view of an opposedcylindersdouble-acting perfectly balanced two-cycle reciprocating engine ofcrankshaft planetary motion system by internal gear according to thefourth embodiment of the present invention, and

FIG. 8 shows a sectional view along line 8-8 of FIG. 7.

V Referring now to FIGS. 1 and 2, a cylinder 1 having a cylinder head 2is secured to a casing 3 through a lower cylinder head 4. A piston 5 isslidably positioned in the cylinder 1 to define upper and lowercombustion chambers 2' and 4' and is secured by such as a pin 6 to upperend of a linearly reciprocating rod 7 having upper and lower seal rings8 and 9 to slidably pass through a center opening of the lower cylinderhead 4. The connecting rod 7 is connected at the lower end thereof to acrank pin 10 of a crank 11. The crank pin 10 lies on a crank axis A andthe crank 11 lies on a crankshaft axis P. The crank 11 provides twocrank arms 12 and 13 which are secured to the crank pin 10 and crankjournals 14 and 15 which are rotatably supported through needle bearing16 and 17 to eccentric collars 1 8 and 19 respectively.

side surfaces of the piston, connecting rod means connected with one endthereof to said piston means and slidably engaging to the wall means,crank means having at least one crank pin each connecting with anotherend of said rod means at a crank radius 1, at least one eccentric collarmeans rotatably supported by said casing and having support meansrotatably supporting the crank means at the same amount ofeccentricity-I, means to cooperate the crank means and the eccentriccollar means to rotate the crank and collar means at the same uniformangular velocity and in reversedirection each other and to effect linearreciprocating motion of the rod means, and balance weight means toeffect above-mentioned perfect balance.

Further and more specific objects, features and advantages of thepresent invention will become apparent in the following description ofpreferred embodiments, by way of example, wherein reference is madetothe accompanying drawing, in which: 5

FIG. 1 shows a longitudinal sectional view along line 1-1 of FIG. 2 of asingle cylinder, double acting, perfectly balanced The eccentric collars18 and 19 provide openings to accommodate the needle bearings 16 and 17at amount of eccentricityl from its axis which is the same length to thecrank radius and are rotatably supported through bearings 20 and 21 bythe casing 3 to rotate on a center axis 0 in the reverse direction andat the same angular velocity to rotation of the crank 11.

To effect rotation and revolution of the crank 11 and to effect linearreciprocating motion of therod 7, gears are provided as shown in FIG. 2.A gear 23 is secured to the outer end of the crank 11 and gears 24 and25are secured to he outer end portions of the eccentric collars 18 and19 respectively. A

shaft 26 is rotatably supported by'the casing 3 and is secured to aneccentric gear 27 having amount of eccentricity-l which meshes with gear23 and has the same number of teeth with that in the gear 23, and gears28 and 29 which have the same number of teeth with that in the gears 24and 25 mesh with gears 30 and 31 which are securedto another shaft 32supported by the casing 3. Also, gears 28 and 29 are secured to theshaft 26. The gears 30 and 31 also mesh'with the gears 24 and 25 so thatthe-eccentric collars 18 and I9 rotate in opposite direction and at thesame angular velocity to rotation of the crank 11. A gear 33 is securedto the shaft 32 and meshes with a gear 34 which is securedtoakick-starting shaft 35.

In this embodiment, the cylinder 1 is constructed as two cycle portscavenging engine. Thus, the cylinder 1 provides an exhaust port 37 andinlet ports, 38 and 39 which are controlled by head 2 and to the lowerend of cylinder a rotary valve 40. The outer periphery of the rotaryvalve: 40 provides gear teeth which meshes through a gear 41 idlysupported by the casing 3 with a gear 42 secured to the eccentric collar19. The inlet ports 38 and 39 are connected through a Roots blower 43 toan inlet passage 44 providing a carburetor 45. Spark plugs 46 and 47 areprovided to the upper cylinder head 2 and to the lower end of cylinder 1respectively.

Balance weights having a total mass m, are secured to the crank arms 12and 13 on the opposite side of the crank pin 10 about the crankshaftaxis P at a distance R from the crank axis A which extends through thecenter of the crank pin 10. Other balance weights having a total mass mare secured to the eccentric collars 18 and 19 on the opposite side ofthe crank journals 14 and 15 at distance R from the crankshaft axis P.As theoretically explained in the above-mentioned related application,the masses m and m are determined to satisfy the formulas ml=m R, and(m+m +m;,)l=m R in which m is the reciprocating mass, m, is rotatingmass exclusive of the balance masses m and m and l is amount ofeccentricity of the eccentric collars l8 and 19 and the crank radius ofthe crank 11. Thus the engine is balanced perfectly.

Operation of the double-acting two-cycle engine shown in FIGS. 1 and 2is as follows:

As shown in FIGS. 1 and 2, the upper combustion chamber 2' is at topdead center, whereas the lower combustion chamber 4 is at bottom deadcenter. At the upper combustion chamber 2',combustion is now takingplace and the piston 5 is pushed downwards. The connecting rod 7 securedto the piston 5 is also moved downward. As shown by arrows in FIG. 2,the energy of the combustion gas is transmitted to the crank 11 and isconverted to rotation of the crank 11 at angular velocity to on the axisP. The gear 23 secured to the outer end of the crank 11 rotatesclockwise with the crank 11 to rotate the eccentric gear 27counterclockwise at the same angular velocity was the gears 23 and 27have the same number of teeth. By rotation of the eccentric gear 27,gears 28 and 29 and the shaft 26 rotate to produce rotation of the gears30 and 31 clockwise on the shaft 32. Thus, the gears 24 and 25 and theeccentric collars l8 and 19 which are supported by the casing 3 throughthe bearings 20 and 21 and supporting the crank 11 through the needlebearings 16 and 17 at the same amount of eccentricallyJ, rotatecounterclockwise at the same angular velocity or on the center axis 0.Thus, the crank 11 rotates on its crankshaft axis P and at the same timerevolves around the center axis at an amount of eccentricity-lthe axis Pin opposite directions and at the same angular velocity to, so thatpoint A or the center of the crank pin 11 at the crank radius I linearlyreciprocates to effect linear reciprocation with a stroke of 41 of theconnecting rod 7. The motion is transmitted to the output shaft 32 asrotating motion.

As the piston moves downward, the piston first opens the exhaust port 37and fresh gas through inlet port 38 is supercharged by the blower 43.After the inlet port 39 is closed off by the piston 5, fresh gas in thelower combustion chamber 4 is compressed until the gas is ignited by thespark plug 47.

At the same time, combusting gas in the upper combustion chamber 2'expands as the downward motion of the piston 5 until the exhaust port 37is opened by the upper side surface of the piston 5 to effect exhaust ofthe spent gas. As the piston 5 opens inlet port 38, fresh gas isintroduced in the combustion chamber 2 to effect scavenging of thechamber 2'.

As the rod 7 reciprocates linearly, gas seal between the lower cylinderhead 4 and the rod 7 can be easily performed by known seal ring means 9,and the combustion gas in the lower combustion chamber produces upwardthrust to the piston 5. Thus, in the upper and lower combustion chambers2' and 4, suction, compression, combustion, exhaust and scavenging cycleare performed at phase difference I80", to produce double-acting cycleinternal combustion engine.

The inlet control of the fresh gas is performed by the rotary valve 40which, in this case, is driven at the same rotation as the eccentriccollar 19 through the gears 41 and 42. To effect good scavenging andsupercharging, the blower 43 is provided in the inlet passage 44, as nosuction pressure is produced in the combustion chambers 2 and 4.

FIGS. 3 and 4 show second embodiment of the present invention utilizinginternal gear to produce linear reciprocating motion of the rod andperfectly balanced feature of the present invention.

In this case, again single cylinder double-acting two-cycle internalcombustion engine is shown for the sake of clarity, however,double-acting four-cycle engine can also be produced easily. The upperportion of the engine is similar to the engine shown in FIGS. 1 and 2,the same reference numerals are used to show same or similar parts orportions.

As shown in FIGS. 3 and 4, a piston 5 accommodating in the cylinder 1and the defining the upper and lower compression chambers 2 and 4 isshown as integral with a connecting rod 7'. .However, in practice, thepiston 5' may be secured to the rod 7' as desired. The lower end of therod 7' is rotatably supported by a crank pin 10' which may be integralwith crank arms 12' and 13 of the crank 11'. Crank journals 14' and 15are supported through needle bearings 16' and 17 by eccentric collars 18and 19' which are supported through bearings 20 and 21' by casing 3respectively.

Gears 50 and 51 are secured to the crank 11' at each side of the crankarms 12' and 13' on the same center P and having pitch circle diameter2! which is twice to the crank radius or to the amount of eccentricityof the eccentric collars. Internal gears 52 and 53 meshing with thegears 50 and 51 and having pitch circle diameter 4l which is equal tothe stroke of the rod 7 and is twice to the pitch circle diameter of thegears 50 and 51, are secured to the casing 3'. Gears 54 and 55 aresecured to the outer end of the eccentric collars l8 and 19respectively. One or both of the gears 54 and 55 are meshed with othergear or gears not shown to drive an output shaft not shown. The rotaryvalve is driven through a gear 56, a shaft 57 which secures the gear 56and is supported by the casing 3', and a gear 58 meshing with the gear55 fixed by the collar 19.

As to balancing of the engine, balance weights having total mass m aresecured to the crank arms 12 and 13 in the opposite side of the crankpin 10' about axis P at distance R from the center of the crank pin 10respectively. Another balance weights having total mass m are secured tothe eccentric collars 18 and 19 in the opposite side of the crankjournals 14' and 15' about axis 0 at distance R from its centerrespectively. The masses m and m are determined, as before, to satisfyabove mentioned formulas mlf=m R and (m+m +m )=m R,, in which m isreciprocating mass, m is rotating mass. Thus the machine is balancedperfectly.

Operation of the double-acting two-cycle engine shown in FIGS. 3 and 4is as follows: 7

As shown, at the upper combustion chamber 2' combustion is now takingplace and the piston 5 and the connecting rod 7' are pushed downward.The crank 11' and the secured planet gears 50 and 51 rotate clockwise onthe center P. At the same time, the planet gears 50 and 51 meshing withthe stationary internal gears 52 and 53 respectively revolve on thecenter 0 counterclockwise. Thus, the eccentric collars l8 and 19' act asplanet carrier of the planet gears 50 and 51 rotating counterclockwiseat the same angular velocity at as the crank 11'. As the pitch circlediameter of the internal gears 52 and 53 is 41 and twice to that of theplanet gears 50 and 51, the connecting rod 7 reciprocates linearly alonglongitudinal axis of the cylinder 1. The output shaft may be connectedto one or both of the gears 54 and 55 which are secured to the eccentriccollars 18 and 19' respectively. A small portion of the driving power isdivided from the gear 55 through the gear 58, the shaft 57 and the gear56 to the rotary valve 40 to control inlet of the fresh gas through theinlet passage 44 providing the carburetor 45 and the blower 43 to theinlet ports 38 and 39.

Combustion and scavenging in the upper and lower combustion chambers 2'and 4' are similar to the engine shown in FIGS. 1 and 2.

FIGS. 5 and 6 show an opposed-cylinders double-acting perfectly balancedtwo-cycle reciprocating engine of crankshaft planetary motion system byeccentric gear according to the third embodiment of the presentinvention.

The engine provides concentrically opposed cylinders 101 and 102 eachsecured to the casing 103. The cylinders 101 and 102 provide inlet ports104 and 105, exhaust ports 106 and 107, and scavenging ports 108 and 109respectively. Cylinder heads 110 and 111 each having a spark plug 112and 113 are secured to the cylinders. The cylinders 101 and 102accommodate pistons 114 and 115 securing to one end of linearlyreciprocating connecting rods 116 and 117 which connect with a crank pin118 of a crank 119 having crank radius 1.

Thus, combustion chambers 120 and 121 are formed between the cylinderheads 110 and 111 and the pistons 114 and 115. The undersides of thecylinders and 102 are sealed by gas seals 124 and 125 which are securedto walls 122 and 123, and connecting rods 116 and 117 are slidablyengaged in gas seals 124 and 125-. Thus precompression chambers 126 and127 are defined between the walls 122 and 123 and undersides of pistons114 and 115.

The crank 119 consists of crank arms 130 and 131, crank pin 118 andcrank journals 132 and 133. The crank journals 132 and 133 are rotatablysupported through needle bearings 138 and 139 to eccentric collars .136and 137 respectively. The eccentric collars 136 and 137 provide openings134 and 135 to accommodate the needle bearings 138 and 139 at amount ofeccentricity-I from its axis which is the same length to the crankradius and are rotatably supported by the casing 103 through bearings140 and 141.

As shown in F165. 5 and 6, a gear 145 is secured to the outer end of thecrank 119 and meshed with an eccentric gear 146 having the same numberof teeth with that in the gear 145 and secured to a shaft 147 which issupported by the casing 103.

Another gear 148 is secured to the shaft 147 and meshes with one ofgears 149 and 150 secured to a shaft 151. Gears 152 and 153 meshing withthe gears 149 and 150 and having the same number of teeth with that inthe gear 148 are secured to the eccentric collars 136 and 137respectively. Output shaft (not shown) may be connected to the shaft151. Also, auxiliary devices such as a generator and/or'a starter may beconnected with the eccentric collar 137.

The operation of the double-acting two-cycle engine shown in FIGS. 5 and6 is as follows:

As shown the piston 114 is at bottom dead center of the combustionchamber 120 an the piston 115 is at top dead center of the combustionchamber 121. Thus, the combustion chamber 120 is scavenging as theexhaust port 106 and the scavenging ports 108 are both opened; theprecompression chamber 126 is at top dead center and the compressedfresh air is delivered to the combustion chamber..120 through thescavenge ports 108. The precompression chamber 127 of the lower cylinder102 is at bottom dead center and fresh gas is supplied to the chamberthroughthe inlet port 105. In the combustion chamber 121 combustion isnow taking place to.

drive the piston 115 and the rod 117.

As the pistons 115 and 114 and the rods 117 and 116 linearly reciprocatealong one longitudinal axis of the cylinders 102 and 101, the rod 116and the piston 114 are directly driven upward by the rod 117. Thedriving force is transmitted to the crank 119, as quiet similar to theengine shown in FIGS. 1 and 2, rotating clockwise. As shown in F IG. 6,the rotation is transmitted to the gear 145, to counterclockwiserotation of the same angular velocity of the eccentric gear 146,rotation of the secured shaft 147, rotation of the gear 148 secured tothe shaft 147 and clockwise rotation of the gears 149 and 150 on theshaft 151, to rotate the gears 152 and 153 counterclockwise, which aresecured to the eccentric collars 136 and 137 respectively, at the sameangular velocity to the gear 145.

As the piston 115 displaces upwards, combustion gas expands, and asthepiston 115 opens the exhaust port 107, the

combustion gas is exhausted. The piston 115 compresses fresh gasintroduced in the precompression chamber 127 after the inlet port 104 isclosed off by the piston. Then, as the piston 115 opens the scavengeports 108, the compressed gas in the precompression chamber 127 isdelivered to the combustion chamber 121 to scavenge and charge thecombustion chamber.

At the same time, compression stroke of the combustion chamber 120 isperformed by the piston 114 in the cylinder 101. After the piston 114closes off the scavenge port 108 and the exhaust port 106, the piston114 compresses fresh gas in the combustion chamber 120 and thecompressed gas is ignited by the spark plug 112 at suitablie timing.Fresh gas is introduced through the inlet port 104 after the pistonopens the port 104.

Thus, the upper and the lower cylinders 101 and 102 are operated astwo-cycle internal combustion engine at l phase difference, each havingprecompression chamber which acts as conventional crankcase compressionchamber. How ever, in this case, as the engine provides two cylinders,conventional crankcase compression can never be utilized. Further,compression ratio of the precompression chambers 126 an 127 can beindependently determined as desired, lubricant mixture ratio can be verylow. Also, as the rods 116 and 117 linearly reciprocate without anyrelative motion, the rods can be secured each other, so that the bearingarea of the crank pin 118 can be determined very small. Consequently,very compact and effective two-cycle engine is provided.

As the piston 114, rods 116 and 117 and piston linearly reciprocate asan integral member without any relative motion, the engine can beregarded as a center output tandem engine which can be .seen as oldfashioned steam engine or a double-acting engine providing a long pistonhaving both side faces opposing to the combustion chambers and 121respectively. As can be seen easily, the tandem engine shown in FIGS. 5and 6 need not long swinging connecting rod and crank mechanism and theengine is perfectly balanced, so that the engine can be easily andadvantageously accommodated to many applications as two-cycle orfour-cycle engines, compressors or pumps. As a double-acting machine,two independent cylinders accommodate a long piston having rigidconnecting rod so that desired characteristic such as precompressionscavenging feature can be provided to both surfaces of the pistonwithout any limitation which has been inevitable in the knowndouble-acting machine, thus, very compact and high output machine can beprovided.

FIGS. 7 and 8 show opposed-cylinders perfectly balanced two-cyclereciprocating engine of crankshaft planetary motion system by internalgear according to he fourth embodiment of the present invention.

The cylinder unit of the engine shown in FIGS. 7 and 8 is shown quitesimilarly to that of FIGS. 5 and 6 for the sake of clarity, so that thesame reference numerals are used to show similar parts or portions.

The cylinders 101 and 102 are secured to a casing 103' in line eachother, so that the connecting rods 116 and 117 connected with crank pin118 of a crank 119' reciprocate linearly along longitudinal axis of thecylinders 101 and 102.

The crank 119' consists of crank arms and 131', crank pin 118 and crankjournals 132' and 133. In this embodiment, gears 160 and 161 havingpitch circle diameter 21 are secured to the crank journals 132' and 133respectively. The crank journals 132' and 133' are rotatably supportedthrough needle bearings 138' and 139 to eccentric collars 136' and 137'respectively. The eccentric collars 136' and 137' provide openings 134and to accommodate the needle bearings and 141' at amount ofeccentricity-l from its axis which is the same length to the crankradius and are rotatably supported by the casing 103' through bearings140' and 141. intemal gears 162 and 163 meshing with gears and 161 andhaving pitch circle diameter 41 are secured concentrically to theeccentric collars 136' and 137'. Gears 164 and 165 are secured to theeccentric collars 136' and 137 respectively to connect output shaft notshown or auxiliary devices not shown.

As to balancing of the engine, balancing weights are secured to thecrank arms and the eccentric collars following to similar processdescribed above, thus perfectly balanced feature is obtained.

Operation of the engine shown in FIGS. 7 and 8 is as follows:

In this embodiment, of the cylinder 101 in the combustion chamber 120 isat top dead center and combustion is now taking place. The combustionenergy is tnansmitted to the piston 114 to push the piston downward,thus, the piston 114, the

connecting rod 116, the connecting rod 117 which displaces with the rod116 without relative motion each other, and the piston 115 movesdownward as an integral member. The linear motion of the pistons androds is transmitted to the crank ll9'to rotate on the axis P, so thatthe planet gears 160 and 161 rotate along the meshing internal gears 162and 163. Thus, the planet carrier or the eccentric collars 136' and 137rotate on the axis at the same angular velocity and in reverse directionto the gears 160 and 161, and the crank 119. Consequently, linearreciprocating motion of the rods 116 and 117 is produced.

Operation of the precompression chamber scavenging twocycle internalcombustion engine providing the cylinders 101 and 102 is perfectlysimilar to the engine shown in FIGS. and 6.

The tandem or double-acting feature described above is also applied tothe reciprocating machine shown in FIGS. 7 and 8.

As the reciprocating machine according to the invention is perfectlybalanced as single cylinder machine, multiple cylinders machine can alsobe produced very easily as perfectly balanced, so that numbers andarrangement of the cylinders can be determined as desired to attaindesired characteristic or to arrange in limited space.

lclaim:

l. A balanced reciprocating machine comprising: a casing; means definingat least one enclosed cylinder secured to said casing; a piston slidablymounted in said cylinder and dividing said cylinder into two workingspaces; means for alternately supplying and exhausting pressurized fluidinto and out of each of said two working spaces to effect reciprocationof said piston; a connecting rod pivotally connected at one end thereofto said piston; crank means including a crank pin connected to the otherend of said connecting rod at a crank radius 1; collar meanseccentrically and rotatably supported by said casing and having supportmeans rotatably supporting said crank means at the same amount ofeccentricity-l; means to rotate said collar means and said crank meansat the same uniform angular velocity and in reverse directions withrespect to each other to effect linear reciprocating motion of saidconnecting rod; a first balance weight having a total mass :11 securedto said crank means on the opposite side of said crank pin at a distanceR, from its axis; a second balance weight having a total mass m securedto said collar means on the opposite side of said support means at adistance R from its axis; and wherein both said balance weights aredetermined in accordance with the formulas mI=m R 1 and (m+m +m )l=mR.-; wherein m is the total reciprocating mass and m is the totalrotating mass exclusive of said balance weights; whereby unbalancedforces caused by said reciprocating mass are balanced.

2. A reciprocating machine as defined in claim 1 wherein said means foralternately supplying and exhausting pressurized fluid comprises atleast one inlet means communicating with said working spaces to supplyfluid into said working spaces and outlet means communicating with saidworking spaces to discharge fluid from said working spaces.

3. A reciprocating machine as defined in claim 2 wherein said cylinderfurther includes ignition means communicating with each of said workingspaces and said outlet means includes exhaust port means alternatelycovered and uncovered by said piston during its reciprocal movement.

4. A perfectly balanced reciprocating machine comprising a casing, atleast one pair of cylinder means having cylinder head means secured tothe casing, each pair of said cylinder means being secured to both sidesof said casing oppositely in line with each other, piston means slidablymounted in each of said cylinder means defining a space between one sideof the piston means and said cylinder head means, rod means connected atone end thereof to said piston means whereby said piston means and saidrod means in said one pair of cylinder means linearly reciprocating asone unit, crank means having at least one crank pin corresponding to thenumber of pairs of said cylinders at a crank radius 1, means rotatablyconnecting each said crank pin to said rod means, at least one eccentriccollar means rotatably supported by said casing and having support meansrotatably supporting said crank means at the same amount ofeccentricity-1, means to rotate said crank and collar means at the sameuniform angular velocity and in reverse directions with respect to eachother to effect linear reciprocating motion of said rod means, balanceweight means having a total mass m secured to said crank means on theopposite side of said crank pin at a distance R from its axis, andwherein both said balance weight means are determined in accordance withthe formulas ml-'m R and (m+m +m )l=M Rf2 wherein m is the totalreciprocating mass and m is the total rotating mass except for saidmasses m and m whereby unbalanced forces caused by reciprocating massare balanced.

5. A reciprocating machine as defined in claim 4 wherein said means torotate said crank means and said eccentric collar means comprises afirst toothed gear secured to said crank means, a first and a secondshaft rotatably supported by said casing and extending parallel to theaxis of said crank means, an eccentric gear having the same number ofteeth as said first gear and having said amount of eccentricity-lsecured to first shaft, second gear means secured to said first shaftthird gear means secured to said second shaft and meshing with saidsecond gear means, and fourth gear means secured to at least one saideccentric collar means and having the same number of teeth as in saidsecond gear means and meshing with said third gear means.

6. A reciprocating machine as defined in claim 4 wherein said means torotate said crank means and the eccentric collar means comprises planetgear means having a pitch circle diameter 21 secured to said crankmeans, and internal gear means secured to said casing concentric to saideccentric collar means and having a pitch circle diameter 4! and meshingwith said planet gear means.

7. A reciprocating machine as defined in claim 4 wherein said machinefurther comprises wall means secured to each of said cylinder meansdefining a further space between said casing and the other side of saidpiston means and slidably accommodating said rod means.

8. A reciprocating machine as defined in claim 7 wherein said cylindermeans further comprises inlet means communicating with said furtherspace, outlet means communicating with said first-mentioned space,scavenge means communicating between said both spaces, and ignitionmeans communicating said first-mentioned space, whereby saidreciprocating machine operates as a two-cycle precompression chamberscavenging internal combustion engine in which each said pair ofcylinders operate at phase difference.

9. A reciprocating engine comprising: a cylinder; a piston mounted forreciprocal movement in said cylinder in response to fluid pressuredifferentials applied thereacross; means for applying fluid pressuredifferentials across said piston to effect reciprocal movement of saidpiston; a rotatably crank mechanism having a rotatably mountedcrankshaft and a crank pin connected thereto at a distance I from thecrankshaft axis; a connecting rod interconnecting said piston and saidcrank pin; rotatably support means having an axis of rotation parallelto and a distance I from said crankshaft axis supporting said crankmechanism for rotation; means for effecting rotation of said crankmechanism and said support means at the same angular velocity but inopposite directions in response to reciprocal movement of said piston; afirst balance weight having a total mess m connected to said crankmechanism at a distance R from said crank pin effective to balance saidengine during rotation of said crankshaft; a second balance weighthaving a total mass m: connected to said support means at a distance Rfrom said crank shaft axis; and wherein both said balance weights aredetermined in accordance with the formulas ml=m R and(m+m +m l=m Rwherein m is the total reciprocating mass and m is the total rotatingmass exclusive of said balance weights; whereby unbalanced forces causedby said reciprocating mass are balanced.

1. A balanced reciprocating machine comprising: a casing; means definingat least one enclosed cylinder secured to said casing; a piston slidablymounted in said cylinder and dividing said cylinder into two workingspaces; means for alternately supplying and exhausting pressurized fluidinto and out of each of said two working spaces to effect reciprocationof said piston; a connecting rod pivotally connected at one end thereofto said piston; crank means including a crank pin connected to the otherend of said connecting rod at a crank radius l; collar meanseccentrically and rotatably supported by said casing and having supportmeans rotatably supporting said crank means at the same amount ofeccentricity-l; means to rotate said collar means and said crank meansat the same uniform angular velocity and in reverse directions withrespect to each other to effect linear reciprocating motion of saidconnecting rod; a first balance weight having a total mass m1 secured tosaid crank means on the opposite side of said crank pin at a distance R1from its axis; a second balance weight having a total mass m2 secured tosaid collar means on the opposite side of said support means at adistance R2 from its axis; and wherein both said balance weights aredetermined in accordance with the formulas ml m1R1 and (m+m1+m3)l m2 R2,wherein m is the total reciprocating mass and m3 is the total rotatingmass exclusive of said balance weights; whereby unbalanced forces causedby said reciprocating mass are balanced.
 2. A reciprocating machine asdefined in claim 1 wherein said means for alternately supplying andexhausting pressurized fluid comprises at least one inlet meanscommunicating with said working spaces to supply fluid into said workingspaces and outlet means communicating with said working spaces todischarge fluid from said working spaces.
 3. A reciprocating machine asdefined in claim 2 wherein said cylinder further includes ignition meanscommunicating with each of said working spaces and said outlet meansincludes exhaust port means alternately covered and uncovered by saidpiston during its reciprocal movement.
 4. A perfectly balancedreciprocating machine comprising a casing, at least one pair of cylindermeans having cylinder head means secured to the casing, each pair ofsaid cylinder means being secured to both sides of said casingoppositely in line with each other, piston means slidably mounted ineach of said cylinder means defining a space between one side of thepiston means and said cylinder head means, rod means connected at oneend therEof to said piston means whereby said piston means and said rodmeans in said one pair of cylinder means linearly reciprocating as oneunit, crank means having at least one crank pin corresponding to thenumber of pairs of said cylinders at a crank radius l, means rotatablyconnecting each said crank pin to said rod means, at least one eccentriccollar means rotatably supported by said casing and having support meansrotatably supporting said crank means at the same amount ofeccentricity-l, means to rotate said crank and collar means at the sameuniform angular velocity and in reverse directions with respect to eachother to effect linear reciprocating motion of said rod means, balanceweight means having a total mass m1, secured to said crank means on theopposite side of said crank pin at a distance R1 from its axis, andwherein both said balance weight means are determined in accordance withthe formulas ml m1 R1 and (m+m1+m3)l M2R2, wherein m is the totalreciprocating mass and m3 is the total rotating mass except for saidmasses m1 and m2, whereby unbalanced forces caused by reciprocating massare balanced.
 5. A reciprocating machine as defined in claim 4 whereinsaid means to rotate said crank means and said eccentric collar meanscomprises a first toothed gear secured to said crank means, a first anda second shaft rotatably supported by said casing and extending parallelto the axis of said crank means, an eccentric gear having the samenumber of teeth as said first gear and having said amount ofeccentricity-l secured to first shaft, second gear means secured to saidfirst shaft third gear means secured to said second shaft and meshingwith said second gear means, and fourth gear means secured to at leastone said eccentric collar means and having the same number of teeth asin said second gear means and meshing with said third gear means.
 6. Areciprocating machine as defined in claim 4 wherein said means to rotatesaid crank means and the eccentric collar means comprises planet gearmeans having a pitch circle diameter 2l secured to said crank means, andinternal gear means secured to said casing concentric to said eccentriccollar means and having a pitch circle diameter 4l and meshing with saidplanet gear means.
 7. A reciprocating machine as defined in claim 4wherein said machine further comprises wall means secured to each ofsaid cylinder means defining a further space between said casing and theother side of said piston means and slidably accommodating said rodmeans.
 8. A reciprocating machine as defined in claim 7 wherein saidcylinder means further comprises inlet means communicating with saidfurther space, outlet means communicating with said first-mentionedspace, scavenge means communicating between said both spaces, andignition means communicating said first-mentioned space, whereby saidreciprocating machine operates as a two-cycle precompression chamberscavenging internal combustion engine in which each said pair ofcylinders operate at 180* phase difference.
 9. A reciprocating enginecomprising: a cylinder; a piston mounted for reciprocal movement in saidcylinder in response to fluid pressure differentials appliedthereacross; means for applying fluid pressure differentials across saidpiston to effect reciprocal movement of said piston; a rotatably crankmechanism having a rotatably mounted crankshaft and a crank pinconnected thereto at a distance l from the crankshaft axis; a connectingrod interconnecting said piston and said crank pin; rotatably supportmeans having an axis of rotation parallel to and a distance l from saidcrankshaft axis supporting said crank mechanism for rotation; means foreffecting rotation of said crank mechanism and said support means at thesame angular velocity but in opposite directions in response toreciprocal movement of saId piston; a first balance weight having atotal mess m1 connected to said crank mechanism at a distance R1 fromsaid crank pin effective to balance said engine during rotation of saidcrankshaft; a second balance weight having a total mass m2 connected tosaid support means at a distance R2 from said crank shaft axis; andwherein both said balance weights are determined in accordance with theformulas ml m1R1 and (m+m1+m3)lm2R2, wherein m is the totalreciprocating mass and m3 is the total rotating mass exclusive of saidbalance weights; whereby unbalanced forces caused by said reciprocatingmass are balanced.